There is little question that the changes in the American demographic structure that occurred in the 1960s would set the stage for a new era in the demographic history of the United States after 1970. In fact, these changes in so many different areas could be said to mark a revolutionary transformation in the demographic history of the nation. The impact of the contraceptive pill and progressively changing norms about women's role in society were two of the factors driving this change. These changing attitudes were reflected in the steady rise of female labor participation rates, of female tertiary education rates, of the median age of first marriage, and of the age when women were having their first children. In turn, these later marriages and pregnancies led to a dramatic decline in fer tility among the white native population, which, for the first time in the history of the country, fell below replacement level. Once the majority established these low fertility norms, they were slowly adopted by almost all the other racial and ethnic minorities and by most immigrants. These low rates have been in place for the past 40 years and show little sign of reversing, especially as they parallel what has been occurring in all advanced industrial societies since the decade of the 1960s.